Experts at the LEDs2009 Conference in San Diego painted a generally rosy picture for LEDs as a growth market, but stressed technical challenges in reliability and efficiency.

In addition, the challenge of dimming strings of LEDs goes well beyond general lighting applications into TV backlighting, and even for energy savings in street lights.

During a Backlighting Summit, keynote speaker Bruce Berkoff, chairman of the LCD TV Association, claimed that analysts are significantly underestimating the demand both for LCD TVs in general and specifically for LED-based, edge-lit, LCD TVs. Berkoff quipped, "In the BRIC (Brazil, Russia, India and China) and Vista (Vietnam, Indonesia, South Africa, Turkey and Argentina) countries, people will buy LCD TVs before they buy indoor plumbing."

Berkoff chastised Samsung for using the LED TV moniker on their LED-lit LCD TVs, but predicted that most of the major TV makers will make a big move to LEDs.

Following the keynote, Displaybank's Jae Shin predicted that LCD TV shipments will reach just over 200 million units by 2012. But Berkoff forecasted a 300 million unit market by 2013, and Displaybank's growth curve is not nearly that steep.

As for the transition to LED backlight or edge light, Berkoff cited several reasons why companies will make the transition. The best LCD TVs use a scanning backlight to minimize the affect called motion blur. It's much easier to use LEDs in such a design than traditional CCFL lamps.

TV makers will also soon use LEDs in a direct backlit design to do what is known as local dimming. Dimming or brightening a select region of the screen based on the level of light in regions of the image being displayed can offer a better picture, according to Berkoff. "Solid-state lighting enhances image processing control," he added.

There are several other reasons for the move to LEDs: they use less power than CCFLs; and they are thinner and weigh less, thereby cutting shipping costs. John Jacobs, director of notebook PC market research at DisplaySearch, said TV makers look for features that allow them to charge a premium price in a market that's headed for commodity status.

As for the near term outlook for LED-based TVs, Berkoff predicted that 1.5 percent of LCD TVs shipped this year would use LED backlights, but that the number will grow to more than 10 percent next year. According to Berkoff, that projection implies that the world supply of LEDs needs to double next year.